arkives1
Member
A planned bike build in spring......
HF2.5 hp engine,5/8 shaft@ 3600 rpm max. Shaft to centrifugal clutch with 10 tooth # 40 sprocket to #40 -17tooth 5/8 bore sprocket on 5/8 jackshaft which goes over to the pedal crank side, then a 9tooth sprocket with 41 chain forward to 44 tooth freewheel screwed onto crank pedal, then 36 tooth #41chain is attached to the 44 tooth equipped freewheel. Chain then goes to the rear wheel which has a 30 tooth freewheel attached. Top speed with a 20 inch OCC chopper wheel is about 30mph.(30.9). For a 26 inch wheel, reverse the positon of the 36 and 30 tooth sprockets, this yields a top speed of 27.9 or use a 48t sprocket on the crank and two 30 tooth sprocket for the drive, this gives 30.7 mph.
These numbers were derived from Jpilot's Gear Ratio Calculator found on this forum and using readily available hardware. I based the wheel diameter as the size given on the tire. The actual diameter may be a bit higher. I do not know if the author of the calculator had figured that in or not. I know the actual diameter of the OCC Chopper wheel is 22.5" approximately.Using that dimension I would use 36 tooth sprockets both front and rear which should give me a top speed of 29 mph.
I used 30 mph top speed as a goal since that's the limit for motorized bicycles here in Wisconsin, other states probably vary.
HF2.5 hp engine,5/8 shaft@ 3600 rpm max. Shaft to centrifugal clutch with 10 tooth # 40 sprocket to #40 -17tooth 5/8 bore sprocket on 5/8 jackshaft which goes over to the pedal crank side, then a 9tooth sprocket with 41 chain forward to 44 tooth freewheel screwed onto crank pedal, then 36 tooth #41chain is attached to the 44 tooth equipped freewheel. Chain then goes to the rear wheel which has a 30 tooth freewheel attached. Top speed with a 20 inch OCC chopper wheel is about 30mph.(30.9). For a 26 inch wheel, reverse the positon of the 36 and 30 tooth sprockets, this yields a top speed of 27.9 or use a 48t sprocket on the crank and two 30 tooth sprocket for the drive, this gives 30.7 mph.
These numbers were derived from Jpilot's Gear Ratio Calculator found on this forum and using readily available hardware. I based the wheel diameter as the size given on the tire. The actual diameter may be a bit higher. I do not know if the author of the calculator had figured that in or not. I know the actual diameter of the OCC Chopper wheel is 22.5" approximately.Using that dimension I would use 36 tooth sprockets both front and rear which should give me a top speed of 29 mph.
I used 30 mph top speed as a goal since that's the limit for motorized bicycles here in Wisconsin, other states probably vary.